| 3891 | |
| 3892 | |
| 3893 | def test_diff(): |
| 3894 | df = pd.DataFrame(np.random.randn(100, 5), columns=list("abcde")) |
| 3895 | ddf = dd.from_pandas(df, 5) |
| 3896 | |
| 3897 | assert_eq(ddf.diff(), df.diff()) |
| 3898 | assert_eq(ddf.diff(0), df.diff(0)) |
| 3899 | assert_eq(ddf.diff(2), df.diff(2)) |
| 3900 | assert_eq(ddf.diff(-2), df.diff(-2)) |
| 3901 | |
| 3902 | assert_eq(ddf.diff(2, axis=1), df.diff(2, axis=1)) |
| 3903 | |
| 3904 | assert_eq(ddf.a.diff(), df.a.diff()) |
| 3905 | assert_eq(ddf.a.diff(0), df.a.diff(0)) |
| 3906 | assert_eq(ddf.a.diff(2), df.a.diff(2)) |
| 3907 | assert_eq(ddf.a.diff(-2), df.a.diff(-2)) |
| 3908 | |
| 3909 | assert ddf.diff(2)._name == ddf.diff(2)._name |
| 3910 | assert ddf.diff(2)._name != ddf.diff(3)._name |
| 3911 | with pytest.raises((TypeError, ValueError)): |
| 3912 | ddf.diff(1.5) |
| 3913 | |
| 3914 | |
| 3915 | def test_shift(): |